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FT4 May Be Too High --- FT3 May Be Too Low

Hi. I am a 41-year-old male, and I have autoimmune hypothyroidism.


From June 2013 to January 2015, I took Synthroid (137 mcg, 3 times per week) (125 mcg, 4 times per week). I also took Vitamin B12 (1000 mcg, 7 times per week). I stopped taking Vitamin D supplements in June 2012.


In January 2015, I had some blood tests, and here are the results:

FT4 = 1.45 (normal range = 0.82 - 1.77)

FT3 = 3.2 (normal range = 2.0 - 4.4)

TSH = 0.075 (normal range = 0.450 - 4.500)

Total T4 = 9.5 (normal range = 4.5 - 12.0)

Vitamin B12 = 1189 (normal range = 211 - 946)


My endo thought that my TSH was too low. So, she lowered my Synthroid dosage to (137 mcg, 2 times per week)
(125 mcg, 5 times per week). I had read that my FT4 was supposed to be in the middle of normal range, but my FT4 was way above the middle. So, I sort of agreed to the lower dosage.

I continued taking Vitamin B12 (1000 mcg, 7 times per week). However, I did skip the Vitamin B12 for 1 week, in order to take the antibiotic Cephalexin.


In May 2015, I had more blood tests, and here are the results:

FT4 = 1.49 (normal range = 0.82 - 1.77)

FT3 = 3.3 (normal range = 2.0 - 4.4)

TSH = 0.088 (normal range = 0.450 - 4.500)

Vitamin D, 25-Hydroxy = 9.6 (normal range = 30.0 - 100.0)

Vitamin B12 = 1148 (normal range = 211 - 946)


I found it very interesting that my FT4 and FT3 levels had gone up, even though my Synthroid dosage had gone down. After the May 2015 tests, my Synthroid and Vitamin B12 dosages remained the same.


Around early August 2015, I was experiencing chest pains and shoulder pains. At one point, I experienced chest pains as I was dissolving a Vitamin B12 lozenge in my mouth. I read that excessive amounts of Vitamin B12 could cause heart problems. I stopped taking Vitamin B12, and the chest pains disappeared. After two weeks of no chest pains, the chest pains returned for about a week. But a doctor (not my endo) listened to my heart and determined that the renewed chest pains were probably caused by anxiety.


About a week ago, I had more blood tests, and here are the results:

FT4 = 1.53 (normal range = 0.82 - 1.77)

FT3 = 3.2 (normal range = 2.0 - 4.4)

TSH = 0.097 (normal range = 0.450 - 4.500)

Vitamin D, 25-Hydroxy = 15.4 (normal range = 30.0 - 100.0)

Vitamin B12 = 700 (normal range = 211 - 946)


My Vitamin D level rose probably because I've been spending time in the summer sun. However, since January 2015, my FT4 has gone from the upper one-third of normal range to the upper one-quarter of normal range, while my FT3 has remained in the middle of normal range (instead of being in the upper one-third of normal range).

As for hypothyroidism symptoms, I've been feeling mentally slower, and I've been getting cramps in my legs and feet. The cramps in my feet that I suffered recently felt very bad and very weird.


So, how do I increase my FT3?

I could try to take a higher dose of Synthroid, but my FT4 may already be too high. I could try to take FT3 medication, but I tried Liothyronine (generic form of Cytomel) a few years ago, and that medication caused me all sorts of heart problems.

Over the past few years, I've been tested for Selenium and Vitamin E and Cortisol (for possible problems with T4-T3 conversion). However, all Selenium and Vitamin E levels were in the lower one-third of normal range, except for one Selenium test in which my Selenium level was in the middle of normal range. And my Cortisol level was in the upper one-tenth of normal range. Because all of these test results were in the normal range, I did not take any Selenium or Vitamin E supplements, and I did not do anything about my Cortisol level. But could the Selenium and Vitamin E levels have been too low in the normal range? And could the Cortisol level have been too high in the normal range? Could there, indeed, be a problem with T4 - T3 conversion?

Could there be a problem with reverse T3? Perhaps an FT3 value of 3.2 is OK. Perhaps I have too much reverse T3 that is interfering with my body's absorption of FT3. Should I be tested for reverse T3?

When I was first diagnosed with hypothyroidism, I took levothyroxine. My first endo told me to take Vitamin D. When the Vitamin D lowered my FT4 and FT3 levels, the endo switched me to Synthroid, hoping the switch would raise my FT4 and FT3 levels. But the switch did not work. My FT4 and FT3 levels went up again only after I stopped taking Vitamin D. But I continued to take Synthroid. Perhaps switching back to levothyroxine will make me feel better?


I have a meeting with my endo in about a week, but, in light of the most recent blood tests, the endo will probably just tell me to stay on the same Synthroid dosage. The endo will probably determine that my hypothyroidism symptoms mean nothing because the FT4 and FT3 levels are in the normal range and the TSH is low. I'm hoping that the people on this forum have some better and more innovative ideas.

Thank you for any assistance.

Best Answer
Avatar universal
Haven't yet finished reading your post thoroughly.  Guess I am a slow reader.  LOL  But a couple of things come to mind.  First is a question about the dosage of T3 that you tried and seemed to have concerns with?  Second is did you split the dose in half for early morning and early afternoon, or did you take the whole dose at once?  Third, have you been tested for ferritin?  And last for now, do you plan to supplement your Vitamin d level to bring it up to optimal, which is about 55-60?
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Avatar universal
"You might be having a problem with the fillers from Levothyroxine.  Maybe you are 'allergic' or reacting to it."


I did some research, and I came upon the following discussion:

healthunlocked (dot) com/thyroiduk/posts/130240096/is-is-possible-to-be-allergic-to-levothyroxine-itself-just-to-the-substance-not-to-fillers

In this discussion, one poster says that she may be allergic to the corn starch that is in levothyroxine.

According to the following website:

www (dot) rxlist (dot) com/synthroid-drug (dot) htm

corn starch is an inactive ingredient in Synthroid (levothyroxine).


But I don't seem to have any reactions to Synthroid. Is corn starch present only in levo? Or in Synthroid as well? Is corn starch present more in levo than in Synthroid?


And what are "fillers"? Are they inactive ingredients? Or are they something else?
Helpful - 0
231441 tn?1333892766
Hi,

You might be having a problem with the fillers from Levothyroxine.  Maybe you are 'allergic' or reacting to it.

D3 should be taken with K2.  Calcium should not affect your thyroid levels (if you take it away from the thyroid meds).  There is some discussion that calcium should not be supplemented and only D3/K2 and the calcium is best coming from diet.

If you are feeling bad on the levo then switch back to synthroid.  

I think you should get your vitamin D levels up to optimal of around 60.  Vitamin D is so important for preventing cancer and other problems.  This may require quite a lot more than 1000 IUI/day.  Then if it does drop your thyroid hormones, your thyroid meds should be adjusted.

You could try different form of B12 also.  There are various forms.  I was prescribe one when I was recently sick in hospital and it made me super itchy.  Yet I have my own health food store  B12 at home and it doesn't have any obvious side effects.

Helpful - 0
Avatar universal
I thought that I would provide an update to this thread.

I met with my endo, and we decided that I would switch back to levothyroxine (manufactured by Mylan). This is the same medication that I took when I was first diagnosed with autoimmune hypothyroidism in 2009. I thought that switching back to levo might make me feel better. My endo had no objection to the switch because she feels that there is no difference between Synthroid and levo.

My levo dose would be the same as my Synthroid dose: (137 mcg, 2 times per week) (125 mcg, 5 times per week). Well, I began taking levo a week ago, and I've been feeling weird ever since. I've been feeling discomfort/pain at the bottom of my heart. And I've felt light-headedness and shortness of breath.

Are these symptoms simply the result of my body trying to adjust to new medication? Or are these symptoms something serious?

I'm supposed to have new blood tests after six weeks of levo, but I don't know whether I can tolerate six weeks of levo. Also, I asked my endo to order a blood test for reverse T3 (rT3) - a test that I would have with the other thyroid tests after six weeks of levo. However, she felt that a bad rT3 level might not be thyroid related, and she didn't want to take any responsibility for non-thyroid matters. So, I will have to purchase the rT3 test privately. But the private rT3 test and the endo-ordered thyroid tests will be done with the same blood draw.

Thanks for any advice.
Helpful - 0
1756321 tn?1547095325
It depends on the person to what side effects B12 may cause. My side effects from B12 injections: three days of severe shortness of breath and a four month acne rash covering my face, chest and belly.  With sublingual B12 spray, I had a headache when I took 3000 mcg after not taking any for a couple of weeks and it took I think maybe two day for that headache to go away.  

I take 2000 mcg daily of sublingual B12 spray.  I have blackheads on my chest and belly from B12 all the time but it's not that bad although it does worsen if I take too much. This could be due to the cyanocobalamin form though but I'm not sure about that.

I'm going to try methlycobalamin sublingual spray from Dr Mercola and see how I go with that. I just found out since going to the gym my B12 is being used up more rapidly and B12 deficiency symptoms are showing even taking 2000 mcg daily so I have to increase the dosage.

Love To Know - Vitamin B12 Side Effects

"The most common side effects of vitamin B 12 supplementation include:

Allergic reactions to preservatives in the preparation for the injection
Mild diarrhea
Anxiety
Panic attacks
Heart palpitations
Insomnia
Breathing problems
Chest pain
Rash and/or hives
Itchy skin
Heartburn
Vomiting
Back pain
Rhinitis (stuffy nose)

In extremely rare cases, the following side effects have been noted:

Congestive heart failure
Pulmonary edema
Peripheral vascular thrombosis (blood clots in the arms and legs)
Folliculitis
Inflammatory acne
Anaphylaxis (most likely related to preservatives used in vitamin B 12 injections)

Because vitamin B 12 is a water soluble supplement, oral supplementation can often lead to bright yellow, strongly scented urine. This is a very common occurrence. Risks of side effects increase with dosage and method of delivery, with vitamin B12 injections having the highest incidence of reported severe side effects and oral supplementation having the lowest incidence of reported side effects, which were mostly mild and transitory."
Helpful - 0
649848 tn?1534633700
COMMUNITY LEADER
You might want to ask your doctor for more clarification on the echocardiogram, but since that was 3 years ago, my suggestion would be to ask for another echocardiogram to make sure that nothing has changed/progressed since 2012 in order to put your mind at rest.

It's a good idea to have an rT3 test done, however, many doctors won't order it.  If you do get one, whether it's ordered by your doctor or if you order it privately, be sure to get Free T3 with it, since a raw rT3 isn't too telling; it's the ratio of FT3:rT3 that's important and the tests need to come from the same blood draw.

Thank you for clarifying your Synthroid dosage.  It appears that, as things stand, right now, you could easily lower that to at least 125 mcg daily, if not a little bit more.  Possibly 125 mcg 5 days/week and 112 mcg 2 days/week, then retest in a month to see if your FT4 is coming down.  

I'm not familiar with the web site you posted regarding vitamin B-12, though I did find that there was negative feedback in regards to it... I have never heard any of the things they report as adverse side effects about B-12 and the worst I've ever heard of is a possible rash in some people; numbness is often caused from longstanding B-12 deficiency (I have worsening peripheral neuropathy due to years of untreated Pernicious Anemia, which is auto-immune B-12 deficiency), so I'll do some research before commenting further on that.

Sally isn't on the forum a lot, so in case she doesn't see your questions about the calcium and vitamin K2... calcium does not, typically, reduce FT3 and FT4 levels as long as you separate your calcium intake from your thyroid medication by at least 4 hours.  There is no test for vitamin K.

If your levels decrease when taking vitamin D, you would probably not need to decrease your thyroid hormone medication.  Since vitamin D is necessary for the proper metabolism of thyroid hormones, increasing your vitamin D levels should help balance your thyroid hormone levels.
Helpful - 0
Avatar universal
"You didn't post any labs from before you started taking the T3 or after you'd been on it, simply that your endo declared you hyper after 3 days on it..."

My endo declared that I was hyperthyroid because of the symptoms that I reported to him.



"Since your cardiac tests all came back within the normal ranges, it's not likely that taking a small amount of T3 is going to cause further damage."

Well, the trace or trivial regurgitation in three valves, by itself, may be normal. But, in addition, some of the 2D measurements were above normal range. And the left and right atria were mildly dilated. Also, my echocardiogram was done after I took the T3. I had never before had an echocardiogram. So, who knows how much damage the T3 did?



"By maintaining a higher than necessary FT4, you do run the risk of driving rT3 too high, since FT4 must be converted to either rT3 or FT3..."

I've never before been tested for RT3. But I will ask my endo about that, and I will make sure to be tested for RT3 the next time I have thyroid tests.
If the endo does not order an RT3 test, I'll buy a private RT3 test.



"I'm somewhat confused as to your exact current dose of Synthroid... could you please clarify that?"

Since January 2015, I've been taking 137 mcg (2 times per week) and 125 mcg (5 times per week).



"I've never heard of too much vitamin B-12 causing chest pain; could you please tell me where you read that?"

www (dot) newhealthguide (dot) org (slash) Vitamin-B12-Overdose (dot) html

• Some of the symptoms of vitamin B12 overdose include itchiness on different body parts and numbness, *improper heart functioning*, giddiness and regular headaches.






Helpful - 0
Avatar universal
In the past, whenever *I* have taken Vitamin D3 supplements, *my* FT4 and FT3 levels decreased. When I stopped taking the Vitamin D3, my levels went back up.

Perhaps *other* people do not experience lowered FT4 and FT3 levels when *they* take Vitamin D3, but my body seems to behave differently.

As for Vitamin K2, I am familiar with Vitamin K2's ability to "direct" the intestinal Calcium that is activated by Vitamin D3. In email, I asked my endo whether Vitamin K2 could prevent the Calcium from lowering my FT4 and FT3 levels. I also asked the endo what kind of Vitamin K2 tests were available. The endo said that did she not have much knowledge of Vitamin K2 and that this was not a test that she usually ordered.

So, let me ask right now. Will Vitamin K2 prevent the Calcium from lowering my FT4 and FT3 levels? What kind of Vitamin K2 tests are available?
Helpful - 0
649848 tn?1534633700
COMMUNITY LEADER
You didn't post any labs from before you started taking the T3 or after you'd been on it, simply that your endo declared you hyper after 3 days on it... which I find rather unlikely, if you really needed it.  It's not the least uncommon for symptoms to worsen or for new ones to appear when changes doses or adding a new med.  Typically, these symptoms would go away, once the body adjusts to having this new medication, which can take days or weeks.

Since your cardiac tests all came back within the normal ranges, it's not likely that taking a small amount of T3 is going to cause further damage.  All 4 of my heart valves have leakage/regurgitation... I have an echocardiogram periodically, to make sure nothing is changing and as long as everything remains stable, I take my 10 mcg/day of T3 without worries (split into 2 doses of 5 mcg/each).  

By maintaining a higher than necessary FT4, you do run the risk of driving rT3 too high, since FT4 must be converted to either rT3 or FT3... Some people are just fine with FT3 at the 50% mark, however, since you seem to have symptoms of being somewhat hypo, you might want to decrease your FT4 and add a small amount of T3 med.  I'd suggest that you start with only 5 mcg/day, divided into 2 doses...  

I'm somewhat confused as to your exact current dose of Synthroid... could you please clarify that?

I agree with Sally, that your vitamin D is way too low... optimal is around 60.  Vitamin D is necessary for the proper metabolism of thyroid hormones.

I've never heard of too much vitamin B-12 causing chest pain; could you please tell me where you read that?
Helpful - 0
231441 tn?1333892766
Hello,

I am only going to comment on Vitamin D, which yours is way too low.

Vitamin D is independent of your thyroid, though low levels are commonly seen in people with autoimmune disease.

Vitamin D affects your immune system.  Therefore strongly recommend that you take a D3/K2 supplement (possibly up to 10,000 IUI/day, and retest in 3 months to see if you are in the optimal range).

Helpful - 0
Avatar universal
Above, I marked gimel's answer as the "Best Answer". I did not intend to mark any answer as the "Best Answer". I simply clicked on my mouse at the wrong time. :) I welcome any and all answers. Thank you.
Helpful - 0
Avatar universal
I took Liothyronine (generic form of Cytomel) in May 2012.

My then-endo wanted me to take 10 mcg of Liothyronine per day (in 5-mcg pills). I would take the first 5-mcg pill with 125 mcg of Synthroid in the morning (I would swallow both pills at the same time). About 6 hours later, I would swallow the second 5-mcg pill of Liothyronine. I would do this every day.

However, to acclimate my body to the Liothyronine, I would spend the first four days taking only one 5-mcg pill, in the morning with the Synthroid. If all went well, I would start taking two 5-mcg pills on day 5.

Also, I would take 1000 mcg of Vitamin B12 and 1000 IU of Vitamin D3, about 12 - 16 hours after the morning Synthroid, three times per week.



On day 1, I took 125 mcg of Synthroid and 5 mcg of Liothyronine. I felt hot to some extent, and I felt some tightness (or pain) in my chest and in my underarm areas. Those feelings continued after I took the Synthroid and Liothyronine on day 2. After the first two days, the feelings of heat and pain were mild, and these feelings were at a level that I thought I could handle.

However, after the third day, my feelings of heat and pain increased, and I felt bad. I woke up on day 4 still feeling bad. So, on day 4, I took the Synthroid but skipped the Liothyronine, and I told the endo how I felt. He said that I was becoming hyperthyroid and that I should stop the Liothyronine, and I agreed.

An EKG showed that I had "voltage criteria for left ventricular hypertrophy (LVH)". LVH is the thickening of the heart's left ventricle, and the EKG showed that it was *possible* that I had it.


An echocardiogram showed that three valves (mitral, tricuspid, and pulmonic) had trace or trivial regurgitation. The left atrial area and the right atrial area were mildly dilated.

For the 2D measurements, some values were above normal range.

The LV ejection fraction was normal. The visually estimated left ventricular ejection fraction was normal at 65 to 70%. I understood this part to mean that I did not have LVH.

My primary doctor declared that this echocardiogram was "normal".



As for Ferritin (serum) tests, I was tested in February 2012 and in March 2013.

The results were as follows:

February 2012 --- Ferritin (serum) = 281 (normal range = 30 - 400 ng/mL)

March 2013 --- Ferritin (serum) = 276 (normal range = 30 - 400 ng/mL)



As for Vitamin D supplements, I am not planning to take any supplements, unless there is a supplement that does not lower my FT4 or FT3 levels.

Helpful - 0
1756321 tn?1547095325
I need free T4 above mid range. Dr Mercola mentions this as well in his article: Optimum Diagnosis and Treatment of Hypothyroidism With Free T3 and Free T4 Levels...

"In order to optimize the hormone replacement, the Free T3 and Free T4 should be above the median but below the upper end of the laboratory normal reference range. The goal for healthy young adults would be to have numbers close to the upper part of the range, and for cardiace and/or elderly patients, the numbers should be in the middle of its range."
Helpful - 0
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